JSON to TypeScript Interface Generator
Convert JSON objects to TypeScript interfaces automatically. Free online tool that generates type-safe TypeScript definitions from any JSON structure.
Frequently Asked Questions
How does JSON to TypeScript conversion work?
This tool analyzes your JSON structure and infers TypeScript types for each value. Strings become 'string', numbers become 'number', booleans become 'boolean', arrays are typed by their element types, and nested objects generate separate interfaces.
Does it handle nested objects?
Yes. Nested objects are extracted into separate named interfaces. For example, if your JSON has a 'user' object with an 'address' sub-object, the tool generates both a User interface and an Address interface with proper type references.
Can it handle arrays?
Yes. The tool inspects array elements to determine the element type. Homogeneous arrays (all strings, all numbers) get typed arrays. Mixed-type arrays or complex objects are handled with union types. Empty arrays default to 'any[]'.
What JSON structures are supported?
Any valid JSON is supported: objects, arrays, nested structures, null values, and primitives. The tool handles optional fields (null values become 'type | null'), arrays of objects, and deeply nested hierarchies.